feat: add max_clients limit per service

README-zh.md

@@ -168,6 +168,7 @@ tls = true # If `true` then it will use settings in `server.transport.tls`
 type = "tcp" # Optional. Same as the client `[client.services.X.type]
 token = "whatever" # Necessary if `server.default_token` not set
 bind_addr = "0.0.0.0:8081" # Necessary. The address of the service is exposed at. Generally only the port needs to be change.
+max_clients = 10 # Optional. 限制此服务的并发连接数。默认值：无限制
 nodelay = true # Optional. Same as the client
 
 [server.services.service2]

README.md

@@ -170,6 +170,7 @@ tls = true # If `true` then it will use settings in `server.transport.tls`
 type = "tcp" # Optional. Same as the client `[client.services.X.type]
 token = "whatever" # Necessary if `server.default_token` not set
 bind_addr = "0.0.0.0:8081" # Necessary. The address of the service is exposed at. Generally only the port needs to be change.
+max_clients = 10 # Optional. Limit the number of concurrent connections for this service. Default: unlimited
 nodelay = true # Optional. Same as the client
 
 [server.services.service2]

examples/max_clients/client.toml

@@ -0,0 +1,6 @@
+[client]
+remote_addr = "127.0.0.1:2333"
+default_token = "simple_test"
+
+[client.services.test_service]
+local_addr = "127.0.0.1:8888"

examples/max_clients/server.toml

@@ -0,0 +1,9 @@
+[server]
+bind_addr = "0.0.0.0:2333"
+default_token = "simple_test"
+heartbeat_interval = 10
+
+# Simple test with single client limit
+[server.services.test_service]
+bind_addr = "0.0.0.0:5555"
+max_clients = 1

src/config.rs

@@ -104,6 +104,9 @@ pub struct ServerServiceConfig {
     pub bind_addr: String,
     pub token: Option<MaskedString>,
     pub nodelay: Option<bool>,
+    /// Maximum number of concurrent client connections allowed for this service.
+    /// None or 0 means unlimited connections (default behavior).
+    pub max_clients: Option<usize>,
 }
 
 impl ServerServiceConfig {

src/protocol.rs

@@ -30,6 +30,7 @@ pub enum Ack {
     Ok,
     ServiceNotExist,
     AuthFailed,
+    ServiceAtFullCapacity,
 }
 
 impl std::fmt::Display for Ack {
@@ -41,6 +42,7 @@ impl std::fmt::Display for Ack {
                 Ack::Ok => "Ok",
                 Ack::ServiceNotExist => "Service not exist",
                 Ack::AuthFailed => "Incorrect token",
+                Ack::ServiceAtFullCapacity => "Service at maximum capacity (max_clients limit reached)",
             }
         )
     }